For example, a liquid crystal panel used for a liquid crystal display device such as a liquid crystal television does not emit light, and thus a backlight unit is required as a separate lighting device. The backlight unit is arranged behind the liquid crystal panel (on a side opposite to a display surface side). The backlight unit includes a chassis having an opening on the side close to the liquid crystal panel, light sources housed in the chassis, a reflection sheet arranged along an inner surface of the chassis to reflect light toward the opening of the chassis, and an optical member (such as a diffuser sheet) provided in the opening of the chassis to effectively exit light emitted from the light source toward the liquid crystal panel side. If LEDs are used as the light sources included in the backlight unit, an LED board on which the LEDs are mounted is housed in the chassis.
The backlight unit including the LEDs as the light sources described in Patent Document 1 below is known, for example.